1. Field of the Invention
The present invention relates to an illumination device and a video presenter, and more particularly, to an illumination device which provides illumination of an object or script placed on a stage, and a video presenter having the illumination device.
2. Description of the Related Art
In general, video presenters are used to present an image on a display device by photographing a 3D actual object or a 2D script placed on a stage using a camera. Unlike a general overhead projector (OHP), the video presenter displays an image of an opaque script or an actual object, or magnifies a 3D actual object or a 2D script and outputs the magnified image to a separate display device. Since a material can be shared with other persons, the video presenter is widely used for presentation.
FIG. 1 is a perspective view of a conventional video presenter. Referring to FIG. 1, the conventional video presenter includes two illumination devices 1, a photographing device 2, and a stage 3. The illumination devices 1 illuminates an actual object or a script placed on the stage 3. The photographing device 2 photographs an image of the actual object or script illuminated by the illumination devices 1. The illumination devices 1 use a fluorescent lamp, a halogen lamp, or a plurality of white high brightness LEDs as a light source. When the illumination devices 1 having the light source are in use, as shown in FIG. 2, light beams are relatively strongly radiated to the left and right sides of the stage 3 while the center portion of the stage 3 receives a relatively weaker light beam. This is because the left and right sides of the stage 3 are close to the illumination devices 1 while the center portion of the stage 3 is far from the illumination devices 1. Thus, the left and right portions of the stage 3 that are close to the illumination devices 1 have a relatively higher luminance while the center portion of the stage 3 that is positioned relatively far from the illumination devices 1 has a relatively lower luminance so that an luminance inconsistent phenomenon occurs.
To reduce the luminance inconsistent phenomenon, as shown in FIG. 3, a difference in the distance between each of the illumination devices 1 and the stage 3 throughout the overall surface of the stage 3 decreases and the distance between each of the illumination devices 1 and the photographing device 2 decreases. However, since light reflected from the surface of a glossy script, for example, vinyl coated paper, glossy paper, or film, placed on the stage 3 is photographed, a glitter phenomenon is generated in a photographed image.
Also, since the light from the illumination devices 1 travels in a space other than the stage 3, the eyes of persons standing around the video presenter may be dazzled.